Correlational finding on Happiness and subject: Time spent on work and care

StudyDeVoe & Pfeffer (2009): study US 2002
TitleWhen Is Happiness About How Much You Earn? The Effect of Hourly Payment on the Money-Happiness Connection.
SourcePersonality and Social Psychology Bulliten, 2009, Vol. 12, 1602 - 1618
PublicWorking people, USA, 2002
SampleProbability stratified sample
Respondents N =15450

Author's labelNumbers of hours worked per week
Page in Source 1607
Our classificationTime spent on work and care
Self report on single question on number of hours 
worked per week
Precise text not presented
Observed distributionM = 42.21, SD = 14.72

Observed Relation with Happiness
O-HL-c-sq-v-4-fr=+.05 ns

Appendix 1: Happiness measures used
CodeFull Text
O-HL-c-sq-v-4-fSelfreport on single question:

If you were to consider your life in general these days, how happy or unhappy would you say you are, on the whole...?
4 very happy
3 fairly happy
2 not very happy
1 not at all happy

Appendix 2: Statistics used
rPRODUCT-MOMENT CORRELATION COEFFICIENT (Also "Pearson's correlation coefficient' or simply 'correlation coefficient')
Type: test statistic.
Measurement level: Correlate: metric, Happiness: metric
Range: [-1; +1]

r = 0 no correlation ,
r = 1 perfect correlation, where high correlate values correspond with high happiness values, and
r = -1 perfect correlation, where high correlate values correspond with low happiness values.
Ruut Veenhoven, World Database of Happiness, Collection of Correlational Findings, Erasmus University Rotterdam.